init research

dataframe/plugins/kotlin-dataframe/testData/box/csDsl/colsAtAnyDepth.kt

@@ -0,0 +1,20 @@
+import org.jetbrains.kotlinx.dataframe.*
+import org.jetbrains.kotlinx.dataframe.annotations.*
+import org.jetbrains.kotlinx.dataframe.api.*
+import org.jetbrains.kotlinx.dataframe.io.*
+
+fun box(): String {
+    val df1 = df.select { name }
+
+    compareSchemas(
+        df1.select { name.firstName and name.lastName },
+        df1.select { name.colsAtAnyDepth() },
+    )
+
+    compareSchemas(
+        df1.select { name and name.firstName and name.lastName },
+        df1.select { colsAtAnyDepth() },
+        df1.select { nameStartsWith("name").colsAtAnyDepth() },
+    )
+    return "OK"
+}